GENERAL ELECTRIC
CLEAR LTV SILICONE COMPOUND FOR POTTING EMBEDDING
Transparent, resilient, supporting, and easy to
AND
self' repair.
A clear, solventless liquid, G-E clear LTV silicone compound cures at 75-80 °C to form a resilient solid with excellent electrical properties. Useful from—65-175° C. LTV is easy to apply, flows freely around complicated parts. Unlike "gellike" potting materials, it cures to a flexible solid. Oven cure is overnight. Pot life is 8 hours.
ITV-602 is easy to work with. To remove embedded parts, merely cut out section, remove or repair part, pour fresh LTV in section, and cure. Excellent shock resistance, and protection against environmental hazards. LTV retains protective properties even after 1800 hours aging at 175°. Resists moisture and water immersion. For full details on General Electric silicone potting and encapsulating materials, including new clear LTV and the widely used RTV liquid silicone rubber compounds, write: General Electric Company, Silicone Products Depr., Section F442, Waterford, New York.
GENERALflELECTRIC 132
C&EN
APRIL
17,
1961
Drink In Some Negative Ions Scientists know that atmospheric ions affect human behavior and suspect that they also influence human performance. They say that negative ions exert a pleasant feeling leading to relaxation and sleepiness. Positive ions, on the other hand, produce an unpleasant feeling accompanied by headache, dizziness, nausea, and sore throat. But how the ions operate— whether the effect on the human body involves electrical, chemical, or hormonal mechanisms—is not known. Two Battelle Memorial Institute scientists—psychologist H. G. Schutz and chemist-meteorologist R. A. Duffee —believe that the next few years will bring an understanding of the effects of atmospheric ions and how they may be used to advantage. Such information could be used to modify the environments men encounter in confined spaces such as nuclear submarines and space ships, they point out. And, they suggest some avenues of research that could lead to the missing links in the ion puzzle. Electrical theories on how ions operate now follow several lines, the Battelle scientists say: One indicates that a biological effect occurs in body cells through a change in conductivity of the cell structure or the electric charge of the cell membrane. Another states that ions act directly on the autonomic nervous system, and, in a third, electricity is "metabolized" through the lining of the lungs and the red corpuscles. The chemical mechanisms suggested to date include these possibilities, according to Dr. Schutz and Mr. Duffee: A change occurs in atmospheric composition because ions are present; a
COMING
change occurs in the activity of atmospheric gases; the ion generator itself produces gases and these gases, rather than ions, produce an effect. One chemical study that Dr. Schutz and Mr. Duffee think holds promise shows that air ionization affects the oxygen-carrying capacity of the blood by altering the relative acidity and alkalinity of the blood and its carbon dioxide combining power. A theory that involves the action of hormones is also well supported in the opinion of the Battelle scientists. This assumes that the effect of ions may be due to an influence on the adrenal cortex and subsequent change in the production of corticoids.
The Royal Scottish Museum in Edinburgh used Ciba's epoxy resin, Araldite, to restore this 17th century Chinese porcelain wine ewer, after it had been broken
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Problems with Lubricants Development of aircraft lubricants that function well at as low as —65° F. and as high as 500° F. presents some knotty problems that chemical research is helping to solve. A C&EN Special Report
